Plastic storage and transport container

ABSTRACT

A transport/shipping box has a polygonal floor with a plurality of straight edges and respective flat walls extending upward from the edges and joined together at corners to form an upwardly directed opening. The walls have upper edges that are of upwardly open U-section.

FIELD OF THE INVENTION

The present invention relates to a box or container. More particularly this invention concerns a plastic storage/transport container.

BACKGROUND OF THE INVENTION

A typical storage and transport container made of plastic normally is of parallepipedal shape with a square or rectangular footprint. Two side walls project parallel to each other from opposite side edges of the floor and two end walls, which normally are shorter than the side walls, project upward from opposite end edges of the floor and are connected at vertical corners to the side walls. The upper edges of the side and end walls define an opening and are intended to fit with the lower edges of a similar box stacked on it to form a stable stack.

In order to achieve the goal of a high degree of container stiffness during favorable production by extrusion, and the capability of being transported via various, known transport systems, many container designs have been created. The standard box unit described above is often used for storage and transport of the most diverse products such as, for example, in the automobile industry for holding parts carriers, deep-draw parts or the like. Flexible containment is achieved for products of different dimensions by providing grid spacers inside the container.

Frequently, large and heavy products require correspondingly dimensioned containers that can have basic dimensions of, for example, 600×500 mm even up to 1000×600 mm. Because the containers must be able to be moved on automatic conveyor belts or on rollers and reels tracks, and the products must be handled by robots, especially in the case of large containers with heavy loads, stability is extremely problematic. In containers known in practice that are designed with a structure of intersecting vertical and horizontal ribs on the outer faces of their walls, and in which a flat upper edge is supported by vertical ribs, it has been shown that when bearing a load, damage to the container is unavoidable.

Due to the upper edge structure, an automatic grab, such as a lifting tools or other special gripper system that acts from the top or from the side, have only a small surface to catch by hook or to grip. This is made even more difficult in that the containers deform starting at the upper edge and/or can even tear, or are distorted inward at the container walls due to their low resistance to bending. Optimal removal of the contents located close to the walls by an automatic gripper or robot is thus extraordinarily difficult, as the gripper/robot would hit the inwardly bent container wall. In addition to making product handling more difficult, the grab itself could be damaged.

If the grab cannot grip the products as intended, failures occur in the automatic systems, as a result of which production is delayed and overall productivity decreased. Although the stability of the container could be improved by using a larger thickness of the material, this, however would not only be associated with additional material and higher production costs, but would also lead to a higher total weight of the container.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide an improved plastic storage and transport container.

Another object is the provision of such an improved plastic storage and transport container that overcomes the above-given disadvantages, in particular that offers in particular, in spite of economical production, a high degree of stability that is also sufficient for transporting and handling heavy products, as well as overall improved features.

SUMMARY OF THE INVENTION

In a transport/shipping box having a polygonal floor with a plurality of straight edges, respective flat walls extending upward from the edges and joined together at corners to form an upwardly directed opening, this object is attained in that the walls have upper edges that are of upwardly open U-section.

Due to this shape or profile of the upper edge, it and thus the entire container has significantly more stability and stiffness, so that deformation of the upper edge because of the forces due to the load that are acting in particular during the condition of being carried, can be avoided. Automatic handling is thus not impaired, because grabs, crane gear or the like can grip the container and the product without interference.

According to an advantageous embodiment of the invention the upper edge defined by the container walls projects outward on one side, so that end sections of the container walls simultaneously form an inner flange of the upper edge. The upper edges of the container walls thus simultaneously also form a part of the upper edge. In contrast, the outer flange of the upper edge extends, according to the invention, parallel to the outer faces of the container walls.

The upper edge that is according to the invention upwardly makes it advantageously possible that water drainage holes can be formed in the floor web of the upper edge, as well as lift holes. The outwardly opening water drainage prevents rain water and dirt from accumulating.

The stability and stiffness of the container can be increased in that the upper edge is divided into compartments or chambers by wall/rib elements extending across the upper edge's full width.

According to a preferred embodiment of the invention, reinforcement strips can be fitted into the upwardly open U-section upper edge, siting flatly on them and secured therein by catch formations. Alternative to this, reinforcement strips can also be designed in accordance with the invention in such a way that after insertion and snapping into the upper edge, sit atop it and cover its entire width. The reinforcement strips, advantageously likewise plastic profiles that are snapped into the upper edge in a simple way with the help of snap tools, lead to an additional increase in the stability of the upper edge or the container. They can be distributed over the entire upper frame, but also precisely targeted by bridging a corner, i.e. starting at a certain position on the facing side over the corner up to a certain position of the adjacent side wall. In this case, the corner sections of the upper edge, which always must withstand very large forces, would be preferentially reinforced, which significantly improves the lateral warp stiffness.

Further, in accordance with the invention, the reinforcement strips can preferably be designed as color-identification means, whereby according to an advantageous embodiment of the invention, at least one snap means of the reinforcement strip engages in a throughgoing catch hole opening to the outside or a through hole of the upper edge. As the marker/reinforcement strips can be provided in different colors, the contents can be immediately defined by means of this color assignment. Thus, each type of content is associated with a certain color that is stored in an identification system. This does not preclude that the container can also be set up to carry a combination of different colors for different types of contents. The marker strips with color identification can be removed if needed, and exchanged if the contents change.

This is not possible with a known color identification system in which plastic containers are provided with color identification on a certain part of the container by means of being hot-stamped, as hot-stamping cannot be removed. Even identification by labels is disadvantageous, as the containers in the stack must necessarily be stacked on top of each other in such a way that the label is always visible and recognizable. In contrast, the through hole of the catch opening for the marker strip that is to be inserted into the upper edge in accordance with the invention offers recognizability that is always visible from the outside, in particular also in the case of containers that are stacked on top of each other. The catch openings or through holes can be provided at any position and in any number. If such marker strips that close the upper edge are not snapped in, rain water can naturally also drain through these through holes in the lower section of the U-profile of the upper edge.

A further preferred embodiment of the invention provides that the stacking edge is designed as a flared inverted-U-section downwardly open profile, whereby its outer flange reaches over the outer flange of upper edge of the lower container while containers are being stacked on top of each other. The stacking edge that is advantageously U-shaped, just like the upper edge, can be provided in alignment with the upper edge at the outer sides of the container walls. Thus the stacking edge of an upper container can be completely put over the upper edge of a lower container. Thus, water is neither able to seep into the lower container, even if no marker/reinforcement strip has been snapped into the upper edge, nor flow into the upwardly open upper edge. Due to the open profiles extending parallel on the top and bottom in opposite directions of upper edge and stacking edge, the container is imparted with such stability and stiffness that additional horizontally extending ribs, which are customary in known containers and which can, for example, get caught in the materials handling devices preventing uniform further transport, can be eliminated.

Finally, it is possible that when stacking containers on top of each other, for example, on a pallet for transport, a protective cover only needs to be placed on the uppermost container of each stacks. Each individual container does not need to be closed with a cover, which can thus, just like subsequent measures, for example, cleaning of the covers, but also storage space and working time can be saved, as the stacked containers are not required to first be individually, manually unstacked for removing the covers and the covers are not required to be placed at a different location for intermediate storage. The containers must then perhaps be stacked onto the pallet again for further transport, in order to, for example, bring them to the robot unloading station. In contrast, during the stacking process of containers on top of each other in accordance with the invention, only the upper protective cover must be removed, after which the pallet with the container stack can immediately be brought to the commissioning station or to the robot removal station. This results in a correspondingly higher availability and lower facility downtime.

BRIEF DESCRIPTION OF THE DRAWING

The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a perspective overall view from above of a container that has an upwardly open upper edge and a flared downwardly open stacking edge (see FIG. 5);

FIG. 2 is a detail of the container of FIG. 1 in a perspective view from above;

FIG. 3 is a perspective detail of an upper corner of the container of FIG. 1 seen from the outside;

FIG. 4 is a perspective detail view of the container of FIG. 1 sectioned through a longitudinal or side wall and showing the U-shaped upper edge in section;

FIG. 5 is a perspective detail view of the container of FIG. 1 sectioned through an entire side wall, i.e. from the upper edge down to the lower stacking edge;

FIG. 6 is a perspective overall top view of a container as shown in FIG. 1, but with marker/reinforcement strips inserted into the upper edge;

FIG. 7 is a perspective overall view of two containers according to the invention stacked on each other and equipped with marker/reinforcement strips;

FIG. 8 is a detail of the container stack of FIG. 7 in a perspective view, sectioned through where the stacking edge of the upper container fits with the upper edge of the lower container;

FIG. 9 a perspective detail view of a marker/reinforcement strip that can be inserted in a corner of the container; and

FIG. 10 is a perspective detail view of the container of FIG. 1 sectioned through a side wall with the U-shaped upper edge and marker/reinforcement strips inserted into the upper edge and completely covering the upper edge, in contrast to the strips of FIG. 6.

SPECIFIC DESCRIPTION

As seen in FIG. 1 a parallepipedal container 1 is integrally produced by extrusion and injection molding. It basically comprises a flat, planar, and rectangular floor 2, two relatively short and generally planar and square end walls 3, and two relatively long and generally planar and rectangular side walls 4. The rectangular upper edge 5 defined by the walls 3 and 4 is U-shaped and upwardly open. A downwardly open and outwardly flared rectangular lower edge 6 can fit down around such an upper edge as shown in FIGS. 5 and 8. Rows 7 of horizontal ridges formed on inner faces of the container walls 3 and 4 make it possible to flexibly hold tool carriers or deep-drawn parts or similar unillustrated elements.

As can be seen more clearly in FIGS. 4 and 5, the upper edge 5 and the lower edge 6 both project outward. Thus inner flanks or flanges 5 a and 6 a of the container walls 3 and 4 are formed as continuations of the respective walls 3 and 4, which themselves are at their most basic flat, planar, and rectangular panels with parallel and planar inner and outer faces. Respective horizontal webs 5 b and 6 b extend outward from lower and upper edges of the flanks 5 a and 6 a and are joined to lower and upper edges of outer flanks or flanges 5 c and 6 c that respectively extend upward and downward parallel to the respective inner flanks 5 a and 6 a, forming the inventive squared-off U-shape that is open upwardly at the upper edge 5 and downwardly at the lower edge 6. The flanges 5 a, 5 c, 6 a, and 6 c are all vertical, planar, and parallel, and in fact as mentioned above the flanges 5 a and 6 a are simply continuations or extensions of the panels forming the respective walls 3 and 4. The floor web 5 b extends perpendicular to the flanges 5 a and 5 c that are substantially identical, but the roof web 6 b extends downward at a small acute angle to the horizontal from the upper edge of the inner flange 6 a to the upper edge of the outer flange 6 c so as not to form a water or dirt trap, and the outer flange 6 c is somewhat longer than the inner flange 6 a to project downward past the respective inner flange 6 a and thus fit around an upper flange 5 as shown in FIG. 8. The outer faces of the walls 3 and 4 have no horizontal ribs, only vertical stiffening ribs 8 that extend between the webs 5 b and 6 b. Thus an automated grab can ride vertically upward along the outer faces without catching on anything until it engages under the stiff upper edge 5.

The upper edge 5 is subdivided by transverse and vertical stiffening ribs or webs 9 into a multiplicity of short upwardly open pockets or chambers 10 so that this upper edge 5 is very stiff, and as shown in FIG. 3, some of the chambers 10 are vertically throughgoing. The web 5 b is formed in the downwardly closed pockets 10 with drainage holes 11. The inner flanges 5 a are formed in some of the chambers 10 on their outer faces with catch formations 12 having a beveled upper face and a perpendicular lower face for engagement with a pickup device or part of a cover. What is more the outer flanges 5 c and floor web 5 b are formed with throughgoing catch openings or slots 13 and 14 as shown in FIGS. 3 and 4.

When two containers 1 are stacked on top of each other, the lower edge 6 of upper container 1 b fits around the upper edge 5 of the lower container 1 a. The outer flange 6 c of the stacking edge 6 somewhat overlaps the outer flange 5 c of the upper edge 5 as shown in FIGS. 7 and 8. This ensures that a stack of the containers 1 will be quite stable.

FIGS. 7 and 8 show stacked containers where the containers 1 that are shown in FIG. 6 are stacked on top of each other, and marker/reinforcement strips 15 a or 15 b are inserted into the U-profile of the upper edge 5 and engage its catch formations 12 or through the holes 13 and catch slots 14 and are thus locked into them. A corner marker/reinforcement strip 15 b that can be snapped in the corner of the upper edge 5 is shown in detail in FIG. 9. It is provided with catch formations 16 complementary to the catch formations 12, as well as with formations 17 and 18 that fit with the catch slots 13 and/or 14 and that are visible there through. Thus the semicircular catch head 18 is easily recognizable from the outside even in the stacking position (see FIG. 7) as a result of fitting with the correspondingly shaped formation 17 or 18 through holes or catch openings 13.

A further embodiment of a marker/reinforcement strip 19 is shown in FIG. 10, which in contrast to the marker strips 15 a or 15 b, bears sits flatly atop the inner flange 5 a and the outer flange 5 c after being inserted into the U-section upper edge 5, so that it covers the upper edge 5 across its entire width. The marker strips 19 are also provided with counter catch formations 20 complementary to catch formation 12 of container 1, and for engaging with catch slots 14 as well as semicircular catch heads 21 fittable through the through holes 13 so as also to be visible from the outside.

The marker/reinforcement strips 15 a, 15 b and 19 are in colors that contrast that of the boxes 1 and that can be of various different colors to allow immediate identification of the container contents from the outside. Since the FIG. 10 marker strips 19 extend over the outer flange 5 c of the upper edge 5 and cover the entire width of upper edge 5, they provide two-dimensional bearing and additionally increase the load bearing capacity when containers 1 are stacked on top of each other. Plus the edge of the top flange of the strip 19 is clearly visible from the side. 

1. In a transport/shipping box having: a polygonal floor with a plurality of straight edges; respective flat walls extending upward from the edges and joined together at corners to form an upwardly directed opening, the improvement wherein the walls have upper edges that are of upwardly open U-section.
 2. The transport/shipping box defined in claim 2 wherein the upper edges are unitarily formed with the walls.
 3. The transport/shipping box defined in claim 1 wherein the side walls are formed as flat substantially panels and each upper edge is formed by an inner flange generally coplanar with the respective panel and an outer flange offset outward from the respective inner flange.
 4. The transport/shipping box defined in claim 3 wherein each outer flange is substantially parallel to the respective inner flange.
 5. The transport/shipping box defined in claim 4 wherein each upper edge further has a horizontal web joining lower edges of the respective inner and outer flanges.
 6. The transport/shipping box defined in claim 5 wherein each upper edge is formed with a plurality of crosswise stiffening ribs unitary with the respective inner edge, outer edge, and web and subdividing each upper edge into a plurality of upwardly open compartments.
 7. The transport/shipping box defined in claim 6 wherein at least some of the compartments are vertically throughgoing in that the respective web is open between the respective ribs.
 8. The transport/shipping box defined in claim 6, further comprising a marker/reinforcement strip fittable in at least one of the compartments and visible from outside the box.
 9. The transport/shipping box defined in claim 8, further comprising interengaging latch formations on the marker/reinforcement strip and on the respective upper edge securing the strip to the respective upper edge.
 10. The transport/shipping box defined in claim 9 wherein the one compartment is formed with a throughgoing hole through which the marker/reinforcement strip is visible.
 11. The transport/shipping box defined in claim 9 wherein the marker/reinforcement strip is of a characteristic identifying color different from that of the box.
 12. The transport/shipping box defined in claim 9 wherein the marker/reinforcement strip is L-shaped, extends around one of the corners and is engaged in two of the chambers.
 13. The transport/shipping box defined in claim 9 wherein the marker/reinforcement strip has a top strip lying atop the inner and outer flanges and visible from outside the box.
 14. The transport/shipping box defined in claim 5 wherein the sides further have downwardly open inverted U-section lower edges engageable over an upper edge of another box.
 15. The transport/shipping box defined in claim 14 wherein the lower edges are formed by inner flanges generally coplanar with the panel of the respective side and outer flanges spaced outward therefrom.
 16. The transport/shipping box defined in claim 15 wherein a spacing between the inner and outer flanges is at least equal to a transverse width of the respective upper edge. 